DEVELOPMENT OF OXIDATION CATALYSTS UTILIZING CHARACTERISTICS OF HETEROPOLY COMPOUNDS

1.合成了单、二、三铁取代的多金属氧酸盐，并对其进行了表征。过氧化氢的利用效率和活性很大程度上取决于铁中心和二铁取代的多金属氧酸盐，基于所使用的底物，gamma-SiW_&lt；10&gt；{Fe(0H_2)}_20_&lt；38&gt；^&lt；6-&gt；，对过氧化氢的利用和转化效率最高。值得注意的是，在DR-铁取代的多金属氧酸盐催化环己烷氧化反应中，过氧化氢对氧化产物的利用率高达100%左右。如此高的效率从来没有报道过。不仅环己烷被催化氧化，而且正己烷、正戊烷和金刚烷也被催化氧化，过氧化氢的利用效率很高。甲烷也通过gamma-SiW_&lt；10&gt；{Fe(OH_2)}_2O_&lt；38&gt；^&lt；6-&gt；.被氧化成甲醇研究还表明，二铁取代的多金属氧酸盐在所用条件下和在过氧化氢存在下是稳定的。Keggin类型的杂多钼酸盐被发现催化分子氧选择性氧化异丁烷。Cs和V的适宜含量分别为2.5和1，Ni的加入提高了异丁烷氧化的催化活性。镍的最佳含量为0.08。结果表明，异丁烷的氧化反应是表面型反应，催化剂表面的氧化能力决定了异丁烷的催化活性。Cs2.5Ni0.08H1.34PVMo11O4O对丙烷氧化也有催化作用。

1. Mono-, di-, and tri-iron-substituted polyoxometalates were synthesized andcharacterized. The efficiency and activity for the utilization of hydrogen peroxide greatly depended on the iron centers and the di-iron-substituted polyoxometalate, gamma-SiW_<10>{Fe(0H_2)}_20_<38>^<6->, showed the highest efficiency of hydrogen peroxide utilization and conversion based on substrates used. It is remarkable that the efficiency of hydrogen peroxide utilization to oxygenated products reached up to ca. 100% for the oxygenation of cyclohexane catalyzed by dr-iron-substituted polyoxometalate. Such a high efficiency has never been reported. Not only cyclohexane but also n-hexane, n-pentane, and adamantane were catalytically oxygenated with high efficiency of hydrogen peroxide utilization.Methane was also oxygenated to methanol by using gamma-SiW_<10>{Fe(OH_2)}_2O_<38>^<6->. It was also suggested that di-iron-substituted polyoxometalate was stable under the conditions used and in the presence of hydrogen peroxide.2. Keggin-type heteropolymolybdates have been found to catalyze the selective oxidation of isobutane with molecular oxygen. The preferable contents of Cs and V are 2.5 and 1, respectively, and the addition of Ni enhanced the catalytic activity for the oxidation of isobutane. The preferred content of Ni was 0.08. It was shown that isobutane oxidation is a surface-type reaction and the catalytic activity is controlled by the oxidizing ability of the catalyst surface. Cs2.5Ni0.08H1.34PVMo11O4O also catalyzed the oxidation of propane.